Gray Whale Periodic Status Review for the - STATE OF WASHINGTON - WDFW
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STATE OF WASHINGTON March 2021
Periodic Status Review for the
Gray Whale
Chris Sato and Gary J. Wiles
Washington Department of
FISH AND WILDLIFE
Wildlife Program
The Washington Department of Fish and Wildlife maintains a list of endangered, threatened, and sensitive
species (Washington Administrative Codes 220-610-010 and 220-200-100). In 1990, the Washington
Wildlife Commission adopted listing procedures developed by a group of citizens, interest groups, and state
and federal agencies (Washington Administrative Code 220-610-110). These procedures include how species
listings will be initiated, criteria for listing and delisting, a requirement for public review, the development of
recovery or management plans, and the periodic review of listed species.
The Washington Department of Fish and Wildlife is directed to conduct reviews of each endangered,
threatened, or sensitive wildlife species at least every five years after the date of its listing by the Washington
Fish and Wildlife Commission. These periodic reviews include an update on the species status to determine
whether the species warrants its current listing or deserves reclassification. The agency notifies the general
public and specific parties interested in the periodic status review, at least one year prior to the end of the
five-year period, so that they may submit new scientific data to be included in the review. The agency notifies
the public of its recommendation at least 30 days prior to presenting the findings to the Fish and Wildlife
Commission. In addition, if the agency determines that new information suggests that the classification of a
species be changed from its present state, the Department prepares documents to determine the environmental
consequences of adopting the recommendations pursuant to requirements of the State Environmental Policy
Act.
The draft periodic status review for the gray whale was reviewed by species experts and was available
for a 90-day public comment period from 28 September to 28 December 2020. All comments received
were considered during the preparation of this revised draft periodic status review. The Fish and Wildlife
Commission voted on 23 April 2021 to maintain the gray whale as sensitive in Washington.
This report should be cited as
Sato, C. and G. J. Wiles. 2021. Periodic status review for the gray whale in Washington. Washington
Department of Fish and Wildlife, Olympia, Washington. 32+ iii pp.
On the cover: whale photo by Christopher Swann; background photo by Surfrider Foundation
This work was supported in part by
personalized and endangered species
license plates
Periodic Status Review for the Gray Whale
in Washington
Prepared by
Chris L. Sato and Gary J. Wiles
Wildlife Program, Diversity Division
Washington Department of Fish and Wildlife
600 Capitol Way North
Olympia, Washington 98501-1091
February 2021
TABLE OF CONTENTS
ACKNOWLEDGMENTS .............................................................................................................................. ii
EXECUTIVE SUMMARY............................................................................................................................. iii
INTRODUCTION ........................................................................................................................................... 1
SPECIES BACKGROUND ........................................................................................................................... 1
NATURAL HISTORY..................................................................................................................................... 3
POPULATION STATUS AND TRENDS .................................................................................................. 6
FACTORS AFFECTING CONTINUED EXISTENCE ......................................................................... 8
MANAGEMENT ACTIVITIES ................................................................................................................. 13
CONCLUSIONS AND RECOMMENDATION .................................................................................... 16
REFERENCES CITED................................................................................................................................. 17
PERSONAL COMMUNICATIONS .......................................................................................................... 31
LIST OF FIGURES
Figure 1. Gray whale mother and calf ........................................................................................................... 1
Figure 2. Hypotheses of gray whale population structure prior to recent information on
movements across the Pacific ......................................................................................................... 2
Figure 3. Routes of 3 WNP gray whales migrating from Sakhalin Island, Russia, to the eastern
North Pacific ..................................................................................................................................... 4
Figure 4. Combined 2019 gray whale strandings in California, Oregon, Washington and Alaska ....... 6
LIST OF TABLES
Table 1. Numbers of gray whale entanglements documented in Washington by location and
time period, 1990–2019 ................................................................................................................. 10
February 2021 Washington Department of Fish and Wildlife
i
ACKNOWLEDGMENTS
Funding for the preparation of this periodic status review came from State Wildlife Grants. We
thank Kristin Wilkinson for providing data and other information on whale strandings, ship strikes,
and entanglements in Washington. Useful information and guidance were provided by John
Calambokidis, Scott Pearson and Steve Stone. Peer review comments were provided by Jim
Carretta, Casey Clark, Victoria Knorr, Aimee Lang, Stephanie Norman, Jon Scordino, Derek
Stinson, Steve Stone, Jessica Stocking, Jennifer Waddell, Kristin Wilkinson, and Nancy Young. We
thank Derek Stinson for designing the report cover.
February 2021 Washington Department of Fish and Wildlife
ii
EXECUTIVE SUMMARY
The gray whale is a large baleen whale that feeds in shallow continental shelf waters and at offshore banks,
where benthic (i.e., bottom-dwelling) invertebrate communities are concentrated. Gray whales are the only
whale species known to feed extensively on benthic animals. They undertake the longest migration of any
mammal, sometimes traveling more than 20,000 km round-trip annually in coastal waters.
Gray whales in the North Pacific are divided into two populations (or stocks) known as the Eastern North
Pacific (ENP) and Western North Pacific (WNP) populations. Both populations were severely depleted prior
to the mid-20th century by harvest during the whaling era. The ENP population migrates along the Pacific
coast of North America between summer feeding grounds in the Bering, Beaufort and Chukchi Seas and
wintering sites along western Baja California and the southern Gulf of California in Mexico, where mating
and calving occur. This stock has recovered from the impacts of whaling, and was estimated at about 26,960
whales in 2016, when it was believed to exist at or near carrying capacity. However, the most recent estimate
(made during the winter of 2019-2020) placed the population’s size at 20,580 animals, revealing a substantial
decline of 23.7% since 2016. This population was federally delisted by the U.S. in 1994.
Within the ENP population, a small aggregation of about 232 individuals known as the Pacific Coast Feeding
Group (PCFG) has been identified. These whales show regular fidelity during the summer and fall feeding
season to waters along the coasts of northern California, Oregon, Washington, and Vancouver Island, British
Columbia, and occasionally as far north as Kodiak Island, Alaska. Genetic testing indicates some
differentiation from the greater ENP population, but PCFG whales likely interbreed with other ENP whales,
and the PCFG is still considered a feeding aggregation of the ENP population.
The WNP population, which is federally classified as endangered by the U.S., primarily feeds in summer in
the Sea of Okhotsk (mostly near the northeastern coast of Sakhalin Island, Russia) and off the southeastern
coast of the Kamchatka Peninsula in the Bering Sea. Although historic records indicate that WNP gray
whales migrated through the coastal waters of Japan and the Korean Peninsula to presumed wintering
grounds off the coast of China, contemporary records of gray whales off Asia are rare. Abundance,
calculated in 2016 to be roughly 271 to 311 individuals one year and older, remains far below pre-whaling
numbers. Although considered genetically distinct from the ENP population, research since 2004 has
detected some members of this population migrating to the Pacific coast of North America to feeding and
wintering grounds traditionally used by the ENP population, and stock identity research is ongoing.
Gray whales face a number of known or potential threats such as entanglement in fishing gear and marine
debris, ship strikes, human-generated marine sound, and climate change. These could adversely impact the
WNP population because of its small size and precarious conservation status. The PCFG is also a concern
due to its small size and the substantial level of uncertainty pertaining to its possible status as a separate stock
under the Marine Mammal Protection Act.
The small WNP gray whale population is federally listed as endangered, and individuals have been seen in
Washington waters. Research has indicated some genetic divergence in the PCFG from the ENP. However,
these uncertainties do not justify any change in status at this time. Given these considerations and the threats
and uncertainties described in this report, it is recommended that this species be retained as a state sensitive
species in Washington. However, uplisting to a higher level of protection may be warranted in the future if
continuing research determines that WNP whales regularly migrate through Washington’s waters and/or the
PCFG is classified as a separate stock.
February 2021 Washington Department of Fish and Wildlife
iiiINTRODUCTION
This periodic status review summarizes the biology, population status, threats, and recent management
actions directed at gray whales (Eschrichtius robustus) in Washington and elsewhere in the species’ range. This
review also assesses whether this species should retain its current sensitive status under state law or be
reclassified. The Washington Department of Fish and Wildlife (WDFW) published a status report for the
gray whale in 1997 (Richardson 1997). That report resulted in downlisting the gray whale from state
endangered to state sensitive.
SPECIES BACKGROUND
This species is a large baleen whale. Adult
males reach 15 m and weigh 16,600 kg.
Adult females reach 15 m in length and
may weigh as much as 34,000 kg when
pregnant (Rice and Wolman 1971, Shirihai
and Jarrett 2006). Adult gray whales are
slate gray and are covered by gray/white
patterns (Figure 1), allowing identification
of individuals. This mottled coloring
occurs naturally as the animal reaches
adulthood and is further enhanced as a
result of crustaceans (‘whale lice’, i.e. Figure 1. Gray whale mother with calf (photo courtesy NOAA).
Cyamidae) and barnacles accumulating on
the skin. Newborn calves average 5 meters in length and are born a dark gray color. They gradually attain
the patchy gray pattern characteristic of adults. Gray whales lack a dorsal fin but have a series of 6 to 12
small humps along the dorsal ridge of the tail stock. Pectoral fins are short and broad. When viewed from
above, the head is V-shaped, with a two-nostril blowhole. Gray whales have only 2 to 5 throat pleats,
distinguishing them from other baleen whale species. The baleen is white to yellow, and roughly 5 to 25 cm
long (Leatherwood and Reeves 1983, Nowak 1991). During the era of commercial whaling, gray whales
gained a reputation as aggressive fighters when attacked, earning the nickname “devilfish” (Scammon 1874).
Taxonomy, populations, and distribution . The gray whale is the sole living member of the family
Eschrichtiidae and is the most primitive of extant baleen whale species (Rice and Wolman 1971, Sumich
2014, ITIS 2017, Kimura et al. 2018). It is descended from filter-feeding whales that appeared at the
beginning of the Oligocene, over 3 million years ago. Gray whales once occurred in both the North Pacific
and the North Atlantic, but the Atlantic population was extinct by the early 18th century (Rice 1998, Swartz
2014). Since 2010, there have been several unexpected sightings of individuals off Israel, Spain, and
Namibia, and a pair in the Laptov Sea off Russia’s Arctic coast (Scheinin et al. 2011, Shpak et al. 2013,
Sumich 2014).
Historically, gray whales in the North Pacific were recognized as two geographically and genetically distinct
populations (or stocks) known as the Eastern North Pacific (ENP) and Western North Pacific (WNP)
populations (Figure 2; LeDuc et al. 2002, Lang et al. 2011, Weller et al. 2013a, 2013b, Carretta et al. 2019).
The ENP population occurs in Washington and migrates along the Pacific coast of North America between
summer feeding grounds in the Bering, Beaufort,Chukchi and Okhotsk Seas and wintering sites along
western Baja California and the southern Gulf of California in Mexico, where mating and calving occur in
February 2021 Washington Department of Fish and Wildlife
1three primary lagoons (Rice and Wolman 1971, Ford 2014, Sumich 2014, Cooke et al. 2017). Animals are
occasionally sighted south of the Baja peninsula along Mexico’s west-central coastline and near Isla Clarion
(Sumich 2014).
Within the ENP population, a small
group of gray whales known as the
Pacific Coast Feeding Group (PCFG)
shows regular fidelity during the
feeding season to waters from northern
California to northern Vancouver
Island; they are also occasionally seen
as far north as at least Kodiak Island,
Alaska (Darling 1984, Gosho et al.
2011, Calambokidis et al. 2015, 2017,
Ford 2014). PCFG members are
Figure 2. Hypotheses of gray whale population structure prior to recent
information on movements across the Pacific (IUCN/IWC Conservation
defined as animals seen within this area
Management Plan). in more than one year during the
months of June through November
between 41°N and 52°N, excluding sightings within the Salish Sea (IWC 2012, Carretta et al. 2019). In
contrast to the main ENP stock, the PCFG does not rely on the dynamics of a sub-arctic ecosystem, and
this uniqueness may provide important flexibility to the species as a whole. The PCFG is recognized as a
distinct feeding group, but its status as separate from the ENP population remains unresolved (Weller et al.
2013b). Recent genetic data indicate that while some matrilineally driven structure exists between the PCFG
and other ENP whales, PCFG whales likely interbreed with other ENP whales (Frasier et al. 2011, D’Intino
et al. 2013, Lang et al. 2014, Lang et al. 2019). Calambokidis et al. (2015) identified nine survey regions
within the PCFG summer range, six of which are located along the coasts of northern California, Oregon
and Washington where PCFG whales are frequently observed. These include areas in Washington off the
outer northwest coast and Strait of Juan de Fuca and another area off Grays Harbor.
About a dozen gray whales known as the “Sounders” visit North Puget Sound each year for 2 to 3 months
to feed on ghost shrimp (Callianassa californiensis). They typically arrive in March and depart by the end of
May, continuing north to Arctic waters for the feeding season. These individuals belong to the main ENP
population and are not considered part of the PCFG (IWC 2012). The Sounders were first sighted in the
early 1990s during a period of high mortality in the gray whale population (Calambokidis et al. 1991, 1992,
2015).
Within the WNP population, the primary summer feeding grounds for gray whales are located in the Sea of
Okhotsk (mainly near the northeastern coast of Sakhalin Island, Russia) and off the southeastern coast of
the Kamchatka Peninsula in the Bering Sea (Weller et al. 1999, 2002, 2013a, Vertyankin et al. 2004,
Tyurneva et al. 2010, Burdin et al. 2013, Lowry et al. 2018). Although historical records indicate that WNP
gray whales migrated through the coastal waters of Japan and the Korean Peninsula to presumed wintering
grounds off the coast of China, contemporary records of gray whales off Asia are rare (Weller et al. 2002,
2013a). Most of these records, including sightings as recent as 2017, are from Japanese waters (Nambu et al.
2010, Nakamura et al. 2017). Only two records of gray whales in Chinese waters have been documented
since the mid-1990s (Zhao 1997, Wang et al. 2015, Zhao et al. 2017), and gray whales have not been
recorded in Korean waters since 1977 (Park 1995, Kim et al. 2013).
February 2021 Washington Department of Fish and Wildlife
2Genetic comparisons of the whales feeding off Sakhalin Island with whales considered part of the ENP
population revealed significant genetic differences, although a limited degree of genetic exchange between
these populations may take place (Lang et al. 2010, 2011). Some whales known to feed off Sakhalin Island
have been recorded in Japanese waters during months when they would presumably be migrating (Weller et
al. 2008, 2016), whereas others have been detected on ENP migratory routes and wintering grounds (Weller
et al. 2012, Urbán et al. 2013, Mate et al. 2015), suggesting that not all gray whales in the WNP population
share a common wintering ground (Weller et al. 2012). These data call into question whether the gray
whales that currently feed in the WNP are surviving members from a population previously thought to be
extinct (Bowen 1974) or are whales born in the ENP that have expanded their feeding range (Mate et al.
2015). Currently most authorities consider the two populations as distinct (Lang et al. 2010, 2011, Weller et
al. 2013b, Mate et al. 2015) and the National Marine Fisheries Service (NMFS) classifies them as separate
stocks under the Marine Mammal Protection Act (MMPA; Carretta et al. 2019). Stock structure is still under
investigation by the International Whaling Commission (IWC) (Cooke et al. 2017).
NATURAL HISTORY
Habitat requirements . Gray whales feed in shallow continental shelf waters and at offshore banks in the
sub-Arctic and Arctic, where benthic (i.e., bottom-dwelling) invertebrate communities are concentrated
(Rice and Wolman 1971, Nerini 1984, Brower et al. 2016). Abundance of prey is a strong factor influencing
summer distribution and habitat use of the whales (Brower et al. 2016). Gray whales are unique from other
baleen whales in that they migrate mainly through coastal and shallow shelf waters, although deeper oceanic
waters are sometimes crossed (Weller et al. 2002, Sumich 2014, Mate et al. 2015). Both summering and
migrating whales are often observed foraging or resting in forests of bull kelp (Nereocystis luetkeana) and other
giant kelp (Macrocystis spp.) in waters 5 to 15 m deep and are also commonly seen near offshore rocks (Ford
2014, Sumich 2014, Scordino et al. 2017). Mating and calving occur in shallow lagoons and bays that
provide warm, protected waters (Rice and Wolman 1971, Rice et al. 1981, Ford 2014, Sumich 2014).
Foraging and diet. All or nearly all feeding occurs during the summer and fall (Akmajian et al. 2012,
Swartz 2014). Gray whales have the most robust baleen of all the baleen whales, and they are the only whale
species known to feed extensively on benthic animals (Rice and Wolman 1971, Ford 2014). They typically
forage on mud, sand, silt or gravel bottoms at depths from the tidal zone to less than 50 m (Rice and
Wolman 1971, Darling et al. 1998, Nelson et al. 2008, Brower et al. 2016). Gray whales feed by rolling on
their side, swimming slowly forward while sucking sediment into the side of their mouth and filtering out
prey through their baleen by pushing out water and mud with their powerful tongues. As they swim, they
dislodge streams of sediment called mud plumes. This method of feeding produces shallow feeding pits in
the ocean floor up to 3 m long and 1.5 m wide that can be seen from aerial photos (Ford 2014, Sumich
2014, Brower et al. 2016). Skim feeding for free-swimming prey such as anchovy at or near the surface is
also practiced.
Ninety genera of prey have been found in the stomachs of gray whales (Nerini 1984). Favored prey are
typically infaunal benthic species found at densities of 100 to 30,000/m3, and up to 440,000/m3 depending
on species (Feyrer and Duffus 2011, Ford 2014, Sumich 2014). Gray whales feed on a variety of
amphipods, as well as mysids (small shrimp-like crustaceans), mollusks, bivalves, polychaete worms, shrimp,
krill and hydroids (Nerini 1984, Darling et al. 1998, Nelson et al. 2008, Brower et al. 2016). They are also
known to feed on anchovy, herring eggs and larvae (Darling et al. 1998, Ford 2014). Gray whales have been
found to consume 250 to 1,100 kg of prey every day, depending on their age and size (Feyrer and Duffus
February 2021 Washington Department of Fish and Wildlife
32011). Fasting whales lose 11 to 29 percent of their body weight during migration and the winter (Rice and
Wolman 1971).
In Washington, PCFG whales prey mostly upon mysids and cumaceans (small shrimp-like crustaceans)
during periods of intense coastal upwelling from early summer to late fall (Brodeur and Ware 1992, Hickey
and Banas 2003, Marchetti et al. 2004, Scordino et al. 2013, 2017). Two favored locations for prey in
Washington are the coast of northwest Washington and the Grays Harbor area (Calambokidis et al. 2015).
In the Salish Sea, a small group of gray whales known as the “Sounders” have been observed foraging
heavily on ghost shrimp on sand flats near the shore off Whidbey and Camano Islands. When the Sounders
arrive, they are typically emaciated. Foraging on ghost shrimp allows the whales to gain considerable body
weight in just a month or two before they continue on to their northern feeding grounds off Alaska. Several
new whales have arrived in recent years to feed on ghost shrimp (Weitkamp et al. 1992, Calambokidis et al.
2015).
Movements. Gray whales undertake the longest migration of any mammal, with most ENP whales
traveling 15,000 to 20,000 km round-trip (Rice and Wolman 1971, Ford 2014, Sumich 2014). The longest
recorded round-trip was made by a WNP female that migrated 22,511 km to Mexico before returning to
Sakhalin Island the next spring (Figure 3; Mate et al. 2015). ENP and some WNP whales begin to leave
their summer feeding grounds in
October and start arriving at
their Mexican breeding sites in
December (Rice and Wolman
1971, Rice et al. 1981, Rugh et al.
2001). Southward migration is
concentrated in December and
January. Swimming around the
clock, animals on their
southbound migration swim at 7
to 9 km per hour and cover 144
to 185 km per day (Ford 2014).
Northward migration extends
from late January to July, with a
peak in April to July
(Calambokidis et al. 2015). At
this time of year, the whales
move steadily at 4 to 5 km per
hour, or 88 and 127 km per day.
Most ENP gray whales migrate
within 10 km of shore, with
northbound travel being closer
to land (Calambokidis et al.
2015). Migrating animals pass
through Washington waters
mainly during November and
December and again from
Figure 3. Routes of 3 WNP whales migrating from Sakhalin Island, Russia, to the eastern March through May (Rice and
North Pacific. The legend depicts departure and arrival/end dates (Mate et al. 2015). Wolman 1971, Ford 2014).
February 2021 Washington Department of Fish and Wildlife
4Migration occurs somewhat farther offshore in Washington than in Oregon (Green et al. 1995). Some
whales enter Willapa Bay, Grays Harbor, the Strait of Juan de Fuca, and Puget Sound during migration.
Females, especially those who are pregnant, generally migrate south earlier than males, and those with calves
remain longer in breeding/birthing areas before starting northward in March (Rice and Wolman 1971,
Sumich 2014). Northbound females with calves remain close to the coastline, navigating through
particularly shallow waters and kelp beds to avoid killer whale (Orcinus orca) attacks (Rice and Wolman 1971,
Sumich 2014). The primary lagoons used by wintering ENP and suspected WNP gray whales are Laguna
Ojo de Liebre (Scammon’s Lagoon), Laguna San Ignacio, and the Bahia Magdalena complex (Rice and
Wolman 1971, Jones 1990, Sumich 2014). Although not well documented, some WNP gray whales are
believed to migrate south to winter breeding grounds off Japan, Korea and China (Andrews 1914, Weller et
al. 2002, 2008). However, some individuals (provisionally 48 percent of the WNP Sakhalin feeding group;
Cooke 2019) migrate to the west coast of North America, which requires a 22,000 km roundtrip to and
from Mexico (Mate et al. 2011, 2015, Weller et al. 2012, Urbán et al. 2013). These movements coincide with
the annual migration of ENP whales and bring WNP animals through Washington’s waters (see
Distribution).
Social organization. Gray whales are usually solitary or occur in small groups of two or three (Ford 2014).
Larger aggregations of as many as 400 individuals may gather at concentrated food sources, but aside from
mother-calf pairs, social bonds are not apparent (Shirihai and Jarrett 2006, Ford 2014, Sumich 2014). Calves
leave their mothers upon weaning at 7 to 9 months of age (Swartz 2014).
Reproduction. Mating activity occurs between November and January during the southward migration
and at the winter breeding and calving grounds (Ford 2014, Sumich 2014), and involves multiple males
competing for females. Sexual maturity occurs between 5 and 11 years of age, with an average of 8 years
(Rice and Wolman 1971, Rice et al. 1981, Ford 2014). After roughly 13 months of gestation, females give
birth to a single calf, which nurses for 7 to 9 months on milk with a particularly high fat content of 53
percent (Rice et al. 1981, Ford 2014). Pregnant females are dependent on their summer fat reserves and do
not feed between foraging seasons. Thus, they must rely on their fat stores from the previous summer to
provide nourishment to their offspring. During years of limited prey availability, fewer females may
reproduce (Rice and Wolman 1971). Gray whale mothers often hold newborn calves to the surface to help
them breathe and are fiercely protective of their young, particularly against predators such as killer whales
and human whalers (Sumich 2014). Calves are born roughly every 2 years between December and February;
however, some may be born during the southward migration (Rice and Wolman 1971). About 5 percent of
the total ENP population is typically comprised of calves (Perryman et al. 2017).
Mortality . Mortality rates are highest for young animals, with an average first-year survival rate of about 71
percent (Punt and Wade 2012). About 75 percent of first-year mortalities occur during the first 2 weeks
after birth. Mortality records for the ENP population indicate that calves represent about 91 percent of
deaths at winter breeding and calving grounds, followed by yearlings (0 to 19.5 percent) and adults (0 to 5
percent) (Jones and Swartz 1984). Annual adult mortality is estimated to be between 0.1 and 5 percent per
year (Punt and Butterworth 2002, Wade 2002). Information on the lifespan of gray whales is limited, but
estimates range from 25 to 80 years (Rice and Wolman 1971, Ford 2014).
Killer whales and humans are the only known predators of gray whales. Killer whales have been observed
attacking individual gray whales both during migration and on feeding grounds (Goley and Straley 1994,
George and Suydam 1998), and are a significant cause of calf mortality (Barrett-Lennard et al. 2011).
February 2021 Washington Department of Fish and Wildlife
5In 1999 and 2000, the ENP population suffered a major population decline, termed an “unusual mortality
event”, or UME. Gray whale strandings along the west coast of North America increased to approximately
seven times the annual mean for 1995-1998, with 283 reported in 1999 and 368 reported in 2000 (LeBoeuf
et al. 2000, Moore et al. 2001, Gulland et al. 2005). Most strandings occurred along the Mexican coast, but
increased strandings were noted in all areas north to Alaska. An unusual aspect of this mortality event was
that most mortalities were adults and juveniles rather than calves. As a consequence of the UME, calf
production was unusually low for 1999 through 2001. The emaciated condition of many whales in 1999 and
2000 suggested that starvation caused most deaths, resulting from either a decreased availability of prey
(Moore et al. 2003) or a disease interfering with foraging. Ultimately, the cause of this UME was
undetermined (LeBoeuf et al. 2000, Moore et al. 2001, Gulland et al. 2005; see Population Status.)
In June 2019, the National Oceanic and
Atmospheric Administration (NOAA)
declared another UME for the ENP
population, spurred by another sharp rise
in strandings along the west coast of
North America. From 2019-March 2021,
there have been 203 strandings along the
U.S. coast (including 48 in Washington),
199 strandings in Mexico, and 16
strandings in Canada (NOAA Fisheries
2021). Strandings in the U.S. were higher
in 2019 (122 strandings) than in 2020 (79
strandings; Figure 4). Although lower
than in the 1999-2000 UME, these
mortalities provide a stark contrast to the
Figure 4. Combined 2019-2021 gray whale strandings in California, Oregon,
average annual number of strandings
Washington and Alaska. from 2001 to 2018. Conditions of the
2019 UME are similar to those of the
earlier event, with some stranded whales showing evidence of starvation and lower calf production in
Mexico. In 2021, 30% of live adult and juvenile whales in two Mexican breeding locations showed signs of
emaciation, compared to 4.9% to 8.2% during 2008-2018 (LSIESP 2021). Mother-and-calf pairs in 2021
numbered about 20 in Bahia Magdalena and Laguna San Ignacio, contrasting with the 75 to 100 pairs found
in these areas in most years (Swartz et al. 2019, LSIESP 2021). Together, these observations suggest that
ENP gray whales have recently experienced poor summer feeding conditions in the North Pacific and
Arctic or may be suffering from the effects of a combination of environmental factors including disease
(Swartz et al. 2019, Christiansen et al. 2021).
Stranding records for gray whales in Washington stand at 284 from 1980 through March 2021 (NOAA
Fisheries 2021). Of these, by far the largest number of records per year occurred during the UMEs in 2019
(34 strandings), 1999 (28 strandings), and 2000 (23 strandings). Strandings likely only represent a fraction of
the true mortality for the population, as many/most animals don’t wash up on shore, or are not
reported/counted.
February 2021 Washington Department of Fish and Wildlife
6POPULATION STATUS AND TRENDS
ENP population . This population decreased from an estimated 12,000 to 24,000 animals before whaling
(Ford 2014) to perhaps just a few thousand animals by the 1930s following intense commercial harvest (see
Commercial and Subsistence Harvest). Genetic research by Alter et al. (2012) suggests a much larger
pre-whaling population of 76,000 to 118,000 whales, but this estimate is not supported by historical harvest
records nor the North American west coast’s probable carrying capacity for the population in recent
decades (Reeves et al. 2010).
Counts made at Granite Canyon south of Carmel, California, since 1967 have produced rigorous estimates
of population size. These indicate that numbers grew from about 10,000 to 13,000 whales between 1967
and 1972 (Reilly et al. 1983) to about 25,000 whales in the mid-1980s, then stabilized at about 20,000 whales
through most of the 1990s. Large numbers of animals died during the UME in 1999 and 2000 (see
Mortality), which caused the size of the stock to decline to about 15,000 to 16,000 whales (Laake et al.
2012, Punt and Wade 2012). However, numbers began to recover immediately and stood at an estimated
20,990 whales (95% probability that the number of whales was between 19,230 and 22,900) in 2011 (Durban
et al. 2013). Growth continued until at least 2016, when the population was estimated at 26,960 animals
(95% probability that the number of whales was between 24,420 and 29,830; Durban et al. 2017). However,
the most recent estimate (made during the winter of 2019-2020) placed the population’s size at 20,580
animals (95% confidence interval of 18,700 to 22,870), revealing a substantial decline of 23.7% since 2016
(Stewart and Weller 2021).
The ENP population is thought to have existed at or near carrying capacity during most years since the mid-
1980s (Moore et al. 2001, Punt and Wade 2012, Carretta et al. 2019). The increase in numbers from 2011 to
2016 may be due to improved feeding conditions caused by warming Arctic waters that have resulted in
higher primary productivity and expansion of ice-free habitat, which has been linked to increases in calf
production in the ENP population (Perryman et al. 2002, Arrigo and Dijken 2015, Moore 2016, Durban et
al. 2017). In contrast, the decline from 2016 to 2020 coincides with the current UME, which is possibly
being caused by a decline in food resources (Christiansen et al. 2021).
The pre- and post-whaling sizes of the PCFG are unknown, but the subgroup has always been small since
its discovery off British Columbia in the 1970s (Hatler and Darling 1974, Darling 1984, Calambokidis et al.
1994). The most recent analyses indicate that the subgroup increased rapidly from 125 (SE = 10.9) in 1998
to 216 (SE = 16.6) individuals in 2004 (Calambokidis et al. 2017, 2019). Annual estimates remained fairly
stable between about 195 (SE = 26.0) and 220 (SE = 12.3) whales through 2012 but increased to an
estimated 250 (SE = 18.2) whales in 2015 (Calambokidis et al. 2019). The most recent estimate of the
PCFG is 232 (SE = 25.2) whales in 2017 (Calambokidis et al. 2019).
WNP population. The pre-whaling size of this population has been estimated at between 1,500 and 10,000
individuals (Yablokov and Bokoslovskaya 1984). Extensive commercial harvest greatly depleted the stock
by the 1930s, with some authors considering it extinct by this time (Bowen 1974, Berzin and Vladimirov
1981, Weller et al. 2002). Hunting continued at low levels until at least 1966 and likely further endangered
the stock (Brownell and Chun 1977). Sightings in the 1980s and 1990s confirmed the continued presence of
the population, but no reliable estimates of numbers were made during this period (Weller et al. 2002).
The 2016 non-calf population was estimated at 271 to 311 individuals, with much of the population (175 to
192 whales) feeding off Sakhalin (Cooke et al. 2018). From 2005 to 2016, the population increased at an
estimated rate of 2 to 5 percent per year (Cooke et al. 2017).
February 2021 Washington Department of Fish and Wildlife
7FACTORS AFFECTING CONTINUED EXISTENCE
Adequacy of existing regulatory mechanisms. Gray whales have benefited from the protections
afforded under a variety of national, international, and state laws. The species is protected under the U.S.
federal MMPA, which, subject to certain exceptions, prohibits the taking (defined as harassing, hunting,
capturing, killing, or attempting to harass, hunt, capture, or kill) and importation of these animals and
products derived from them. The MMPA authorizes take under a variety of circumstances, including Alaska
tribal subsistence harvest and incidental take during commercial fishing operations and some other
circumstances. Under the MMPA, the WNP stock is considered “depleted” and is treated as a “strategic
stock” by virtue of its listing under the Endangered Species Act (ESA); the ENP stock does not carry
similar designations. Although PCFG gray whales are considered a distinct feeding group, they currently do
not have formal status under the MMPA (Carretta et al. 2019). The species was federally listed as
endangered in 1970 under the Endangered Species Conservation Act of 1969, which preceded the
Endangered Species Act of 1973. The ENP population was delisted in 1994 (USFWS and NMFS 1994), but
the WNP population remains listed as endangered under the ESA. Federal endangered status includes
prohibitions on take of listed species similar to those under the MMPA. NMFS has not designated critical
habitat for gray whales.
National marine sanctuary regulations (15 CFR 922 Subpart O, 152(a)), which apply to the Olympic Coast
National Marine Sanctuary off the outer northwest coast of Washington, contain prohibitions on the taking
and possessing of any marine mammal in the sanctuary, except as authorized by the MMPA and ESA, or
allowed through tribal treaty rights.
Under Washington state law (WAC 220-610-010), gray whales were listed as endangered in 1981, then
downlisted to sensitive status in 1997. A sensitive classification prohibits the intentional taking, harassment,
or possession of the species (RCW 77.15.130). Gray whales are considered a priority species under
WDFW’s Priority Habitats and Species program, but specific management recommendations for them have
not been developed under this program.
The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) specifies the ENP population
is not at risk, but the PCFG is endangered due to genetic differences, and the WNP population is
endangered. The species is on the British Columbia Blue List, meaning that it is especially sensitive to
natural events or various human impacts. Mexico initiated protections for different lagoons used by gray
whales beginning in the 1970s, then declared its territorial seas and Economic Exclusion Zone as a refuge
for all species of large whales in 2002. Russia, Japan, South Korea, and China also offer different levels of
protection for the species in their territorial seas (Swartz 2014).
Protection from commercial harvest was extended to gray whales under the International Convention for
the Regulation of Whaling in 1946 (implemented in the U.S. via the Whaling Convention Act [WCA]). The
International Union for the Conservation of Nature (IUCN) categorizes the entire gray whale species as
Least Concern, but considers the WNP population as Critically Endangered. Gray whales are also listed on
Appendix I of the Convention on the International Trade of Endangered Species of Wild Fauna and Flora
(CITES), which bans international commercial trade in products from this species.
Commercial and subsistence harvest. Commercial whaling during the 19th and 20th centuries decimated
many populations of whales worldwide (Roman and Palumbi 2003, Rocha et al. 2014). Commercial
February 2021 Washington Department of Fish and Wildlife
8exploitation of the ENP population began after the discovery of its winter breeding and calving grounds in
Baja California, Mexico, in 1845-1846. Harvest intensified in the ensuing years and expanded northward to
California and beyond, with an estimated 6,100 to 8,300 animals taken by 1874 (Reeves et al. 2010, Punt and
Wade 2012). Concentrations of females with calves were particularly vulnerable during these years, which
reduced the reproductive capacity of the population. Harvests fell substantially by the mid-1870s and the
stock was considered commercially extinct by 1900. Harvest increased again in the 1920s with the advent of
modern factory-ship whaling, resulting in more than 1,000 additional whales being killed by 1946 (Reeves et
al. 2010, Punt and Wade 2012). Some additional harvest occurred from the late 1940s to 1970s for research
and from illegal Soviet whaling (Wolman 1985, Ivashchenko et al. 2013). Harvest was minimal during the
shore-whaling era off Washington (1911-1925) and British Columbia (1908-1967), with perhaps just a single
gray whale caught by whalers from Bay City, Washington, and about a dozen taken off British Columbia
(Scheffer and Slipp 1948, Pike and MacAskie 1969). These small harvests were likely caused by a
combination of factors, including the stock’s reduced size, the species’ lower desirability to whalers and its
use of nearshore waters, and because the migration did not strongly overlap with the main whaling season
(Scheffer and Slipp 1948).
Commercial hunting of the WNP population from the 1500s until 1966 nearly eliminated this population
(Kato and Kasuya 2002, Weller et al. 2002). Although not well documented, commercial whaling may have
played a role in the extirpation of gray whales from the North Atlantic by the early 1700s (Swartz 2014).
Gray whales have been hunted for subsistence purposes by coastal native peoples of western North
American and Siberia for thousands of years (Jones and Swartz 2002, Ford 2014). Gray whales and
humpback whales (Megaptera novaeangliae) constituted major food items for the Makah Tribe along
Washington’s northwest coast for at least 1,500 years, as indicated by oral and written accounts and
archaeological evidence (Swan 1870, Scheffer and Slipp 1948, Huelsbeck 1988, 1994). The number of gray
whales historically harvested by Native Americans in Washington is not well documented, but some reports
suggest it could have been substantial (Collins 1996, Webb 2011). Subsistence hunting of the ENP
population continues to the present, primarily by Chukotka Natives in northeastern Russia who have
harvested approximately 125 whales per year since 1998 (IWC 2018). The current IWC Schedule for ENP
gray whales establishes a 7-year catch limit of 980 whales for 2019 through 2025 (including an annual
maximum of 140 whales) for the Russian Federation and the U.S. (Carretta et al. 2019); a bilateral agreement
between the two countries allocates up to 135 whales per year to the Chukotka Natives and up to 5 whales
per year to the Makah Tribe. This level of harvest is considered sustainable (IWC 2013). Two gray whales
have been taken by Makah hunters in recent years, one during an authorized hunt in 1999 and one during an
unauthorized hunt in 2007. In 2005 the Makah Tribe submitted a request to NMFS for authorization under
the MMPA to resume treaty-based hunting of ENP gray whales, which received extensive NMFS review
(NMFS 2015). In April 2019, NMFS published a proposed rule to allow the Makah to hunt one to three
whales per year over a 10-year period, with measures included to reduce the likelihood of taking WNP and
PCFG whales (NMFS 2019). In February 2020, NOAA Fisheries published a notice of intent to prepare a
supplement to the Supplemental Draft Environmental Impact Statement (DEIS) issued on March 30, 2015.
Upon release, NMFS will provide a 45-day public review/comment period.
Entanglement in fishing gear and marine debris. A growing concern to whale populations is the level
of threat posed by entanglement in active drifting or stationary fishing gear (such as gillnets and vertical lines
used in trap/pot fisheries) or in discarded netting and other marine debris (IWC 2010, Williams et al. 2011b,
Reeves et al. 2013). Death, injury, or eventual starvation may result when entangled animals fail to free
themselves of gear or debris. Risk of entanglement varies with species, the amount of overlap with various
February 2021 Washington Department of Fish and Wildlife
9fisheries, and the type of gear used in those fisheries. More entanglements are reported in coastal and
continental shelf waters than in waters farther offshore (Saez et al. 2021). In some whale populations,
roughly half or more of all individuals show scarring from past entanglements (Neilson et al. 2009, Weller et
al. 2009).
Gray whales are especially vulnerable to entanglement because of their use of nearshore coastal waters,
where fishing activity is often highest. From 1982 to 2018, gray whales were the most frequently entangled
whale species along California, Oregon, and Washington, averaging 6.9 entanglement reports per year
(NMFS, unpublished data), although actual numbers of entanglements are likely much higher than indicated
by these reports. Most entanglement reports are received from January to May, which coincides with the
species’ northbound migration (Saez et al. 2021). The vast majority are documented off California, but this
is due in part to California’s larger number of observers on the water and longer coastline than in
Washington and Oregon (Carretta et al. 2017, NOAA Fisheries 2019, Saez et al. 2021). Most gray
entanglements since the late 1990’s involve trap/fishing gear that cannot be identified, but of the
entanglements for which gear can be identified, the majority have been attributed to trap/pot fisheries,
especially from commercial Dungeness crab fisheries (NOAA Fisheries 2017, Saez et al. 2021).
Entanglements have involved some PCFG whales (Saez et al. 2021). Whales have been known to carry gear
for hundreds, or even a thousand or more kilometers, from the site of the entanglement to the location
where they are reported (Saez et al 2013).
In Washington, 24 of the 47 large whale entanglements reported since 1990 have involved gray whales.
Incident reports have increased since 2000, and more incidents have occurred along the outer coast than in
the Salish Sea (Table 1).
Available evidence suggests that entanglements of Table 1. Numbers of gray whale entanglement reports
WNP gray whales off eastern Asia may be an documented in Washington by location and time
important limiting factor on this population period, 1990–2020 (NMFS, unpublished data).
(Weller et al. 2008, 2014, Bradford et al. 2009,
Carretta et al. 2017, Lowry et al. 2018) and could Location Time period
be slowing or preventing its recovery (Thomas et Outer Salish 1990- 2000- 2010-
al. 2016). Extensive coastal net fisheries occur in Total coast Sea 1999 2009 2020
parts of the stock’s distribution (Weller et al. 24 20 4 2 10 12
2002).
Vessel strikes. Whales swimming or resting near the ocean surface can be vulnerable to injury or death
from collisions with large and small vessels, especially in areas of frequent vessel traffic such as the U.S. west
coast. Collisions can involve either blunt force trauma or propeller strikes. Ship strikes of whales have
become more common in recent decades due to increases in shipping traffic, ship speeds, and whale
abundance (Laist et al. 2001, Calambokidis 2011, Neilson et al. 2012). Documented collisions and resulting
mortalities undoubtedly represent just a small fraction of the total number (Jensen and Silber 2004, Williams
et al. 2011a).
Gray whales are one of the whale species most commonly struck by ships between California and
Washington (Jensen and Silber 2004, Douglas et al. 2008, DeAngelis et al. 2011), whereas fewer collisions
are known from Alaska (Neilson et al. 2012). Along Washington’s outer coast, major shipping lanes
converge from several directions into the mouths of the Strait of Juan de Fuca and Columbia River, and
another follows a north-south route to California. Douglas et al. (2008) listed six gray whale strandings in
February 2021 Washington Department of Fish and Wildlife
10Washington involving collisions from 1980 to 2006, and Carretta et al. (2017, 2018) reported 11 known
deaths and eight injuries from vessel collisions across the full range of the ENP population from 2008 to
2016, including three possible members of the PCFG. Vessel strike risk along Washington’s coast is highest
during the feeding period (June to October) (Silber et al. 2021). The Salish Sea is also an area of heavy
vessel traffic. Extensive shipping traffic within widespread portions of the range of WNP population means
that ship strikes are an important threat for these whales as well (Silber et al. 2021).
Disturbance from sound and vessels. Marine mammals in all oceans are exposed to increasing levels of
underwater sound from vessels, seismic surveys, sonar, marine construction, and other human-related
sources (Nowacek et al. 2007, 2015). Marine ambient noise levels at frequencies below 500 Hz, which
overlap with the low-frequency calls of baleen whales, have increased by at least 20 dB (re 1 µPa) since pre-
industrial conditions (Hildebrand 2009), including along much of the North American west coast (Andrew
et al. 2011, Redfern et al. 2017). Baleen whales rely on their acoustic sensory system for communicating
with other individuals, sometimes at distances of hundreds of kilometers. Significant levels of
anthropogenic sound can therefore interfere with communication by masking vocalizations (Erbe et al.
2016). Intense sound can also cause changes in surface, foraging, and vocal behavior, displace animals from
occupied areas, and produce temporary or permanent hearing damage and physiological stress (e.g.,
Nowacek et al. 2007, Castellote et al. 2012, Risch et al. 2012, Rolland et al. 2012). Where sound-related
impacts are severe, reproduction and survival of animals may be affected (Clark et al. 2009). Nevertheless,
responses by whales can vary depending on localized circumstances, sometimes with no observable
reactions recorded (Nowacek et al. 2007). For the past ten years and the next seven years (at a minimum),
the U.S. Navy has authorized incidental take (i.e., harassment) of Gray Whales, Humpback Whales, and
other marine mammals resulting from its training and testing activities including the use of sonar and other
transducers, in-water detonations, and potential vessel strikes.
Throughout their range, gray whales face increasing sound levels associated with expanding vessel traffic, oil
and gas exploration and development, wind farm construction, other coastal development, and military
training (Ford 2014, Swartz 2014, Muir et al. 2016). Noise from these activities has been shown to cause
avoidance behavior and changes in acoustic call characteristics of this species (Moore and Clarke 2002,
Dahlheim and Castellote 2016).
The tremendous growth in whale watching in recent decades (O’Connor et al. 2009) has brought increasing
concern over disturbance caused to cetaceans, which can result from the physical presence and sound of
whale-watching vessels (Parsons 2012, Hoyt and Parsons 2014). Whale watchers frequently target gray
whales on their Mexican breeding and calving grounds and during migration past California, but viewing
pressure from Oregon to Alaska is generally limited to areas near a few ports with whale-watching
companies (O’Connor et al. 2009). The small numbers of gray whales using the Salish Sea are regularly
targeted, but much less so than killer whales, although viewing pressure may increase with the
implementation of new regulations aimed at protecting southern resident killer whales. Vessel-based whale
watching has been documented to cause changes in the species’ swimming behavior (Heckel et al. 2001,
Moore and Clarke 2002, Sullivan and Torres 2018), but overall the activity does not appear to be an
important concern in the conservation of the species.
Climate change. Global climate change is likely to be one of the greatest threats to many species of
marine mammals in the coming decades from alteration of marine ecosystems and food webs through
changes in ocean temperatures, currents, stratification, and nutrient cycling, and increased frequency of
unusual ocean conditions such as strong El Niño events (Doney et al. 2012) and marine heatwaves. Climate
February 2021 Washington Department of Fish and Wildlife
11change effects on oceans will probably occur unevenly, with some areas affected more severely than others.
Declining summer sea ice and warming ocean temperatures may allow gray whales to expand their foraging
range farther into the Arctic, but will also likely bring changes in prey abundance and availability and
possibly increased competition for prey with other baleen whale species as they also expand northward
(Brower et al. 2016, Moore 2016). However, the adaptable feeding strategies of gray whales may limit the
negative impacts from these concerns (Swartz 2014). Reductions in sea ice are also expected to boost
human activity in the Arctic (e.g., oil and gas exploration, shipping traffic, commercial fishing), resulting in
increased ocean noise levels and a greater likelihood of oil spills, other forms of environmental degradation,
and ship strikes (Clarke et al. 2013). Increased exposure to novel diseases throughout the species’ range is
an additional possible outcome of climate change (Simmonds and Eliott 2009). A concern related to climate
change, increasing ocean acidification, is currently not considered an important future threat to marine
mammals off western North America (Marshall et al. 2017).
Small population size. The small size of the WNP population imparts a higher risk of inbreeding, loss of
genetic variability, and occurrence of chance events such as demographic fluctuations and population-level
impacts from ship strikes and entanglements, all of which could negatively affect the stock. The PCFG is
also relatively small and could be affected in similar ways.
Environmental contaminants. Marine mammals are susceptible to a variety of environmental
contaminants that bioaccumulate upward through marine food webs (O’Hara and O’Shea 2001, Buckman et
al. 2011, Mongillo et al. 2016). These substances include organochlorines (e.g., polychlorinated biphenyls
[PCBs], dioxins, dichloro-diphenyl trichloroethane [DDT] and its derivatives, and various other pesticides
and herbicides), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons, trace metals
(e.g., mercury, cadmium, copper), and other emerging pollutants (O’Shea 1999, O’Hara and O’Shea 2001).
High contaminant levels can be harmful to the health of marine mammals, but baleen whales typically carry
smaller pollutant loads than toothed whales because of their lower position in food chains. As with most
other baleen whales, gray whales appear to possess relatively low toxicant loads that are beneath those
associated with health disorders in other species (Wolman and Wilson 1970, Varanasi et al. 1994, Krahn et
al. 2001, Tilbury et al. 2002). Contaminant concentrations can vary among individuals and may be higher in
diseased or aged animals in poor nutritional health. Small numbers of gray whales harvested by Chukotka
Natives in northeastern Russia are known as “stinky whales” and possess a medicinal odor to their tissues,
making them inedible (NMFS 2015). This phenomenon remains under investigation but may possibly be
caused by diet or exposure to hydrocarbons (NMFS 2015).
Oil spills. At the population level, marine oil spills are generally considered a relatively minor threat for
large whales, with few if any harmful impacts reported in the literature. Nevertheless, when exposed to oil,
individual whales can experience baleen fouling, ingestion of oil, respiratory distress from inhalation of
vapors at the water’s surface, and contaminated food sources (Geraci 1990, Takeshita et al. 2017), all of
which may produce physiological effects that remain poorly understood. Major spills may cause lingering
reproductive and health impacts (Kellar et al. 2017, Smith et al. 2017), as well as direct mortality of prey and
displacement from feeding areas.
As a shipping and oil-refining hub, Washington experienced seven major oil spills ranging from 0.1–2.3
million gallons along the outer coast, the Strait of Juan de Fuca, and the lower Columbia River between
1964 and 1991 (Neel et al. 2007). It is unknown whether any of these harmed gray whales. Increased safety
measures and prevention programs since the 1990s have helped reduce the number and scale of vessel spills
in Washington, where no spills exceeding 100,000 gallons have occurred since 1991 (Etkin and Neel 2001,
February 2021 Washington Department of Fish and Wildlife
12Neel et al. 2007). However, the sheer volume of shipping traffic (i.e., nearly 7,100 vessel transits in 2018;
WSDOE 2019) makes oil spills a persistent threat in the state. Shipping routes for major ports in Seattle,
Tacoma, and Vancouver, B.C., as well as several major oil refineries and the third largest naval base in the
U.S., all traverse waters used by gray whales in Washington. A 2015 risk assessment of oil spills from vessels
transiting the Salish Sea and northern outer coast of Washington found that the region remains at risk of a
large spill (Van Dorp and Merrick 2017). Spill risk in Washington’s marine habitats is expected to increase
substantially in the future as tanker traffic from ports in British Columbia and possibly Washington
increases due to expanded oil and natural gas production in the interior of North America, and expansion of
the TransMountain oil pipeline that terminates at Burnaby, BC.
Harmful algal blooms. Harmful algal blooms, also known as “red tides,” result from rapid, temporary
increases in local populations of particular dinoflagellates, protists, or other phytoplankton. Two of the
most common toxins produced by algal blooms along the west coast of North America are the neurotoxins
domoic acid and saxitoxin, both of which can be toxic to marine mammals, especially pinnipeds (Torres de
la Riva et al. 2009, Lewitus et al. 2012). Although few known cases of acute algal poisoning have been
confirmed among gray and other large whales (Gulland et al. 2005, Fire et al. 2010, Lewitus et al. 2012),
there have been increasing reports of both toxins being detected in whales and blooms coinciding with
whale mortalities (Lefebvre et al. 2016, Wilson et al. 2016). Harmful algal blooms are projected to become
increasingly common in the future with warming ocean conditions (McKibben et al. 2017) and therefore
could represent a possible emerging concern for gray whales.
MANAGEMENT ACTIVITIES
Management of whaling. International moratoriums on the commercial harvest of gray whales (in 1946)
and all large whales (in 1986) were established by the IWC and remain in effect as a primary conservation
tool. Subsistence harvest of gray whales by native peoples of the Russian Federation (Chukotkans) and the
U.S. (Makah) is based on a joint request by the two countries and managed through a quota system
established by the IWC for aboriginal whaling. That system relies on advice from an IWC scientific
committee to establish a 6-year quota with annual catch limits. The Makah Tribe reserved the right to hunt
gray whales at its usual and accustomed grounds under the Treaty of Neah Bay in 1855. A combination of
factors (including the ENP population decline noted above) led to the suspension of Makah whaling in the
1920s. The Tribe resumed whaling in 1999 and 2000 but has not been authorized to hunt since 2004 due to
court rulings requiring that the waiver and permit provisions of the MMPA be satisfied before NMFS can
authorize a hunt. In 2005 the Tribe applied for authorization under the MMPA and WCA to harvest up to
20 ENP gray whales over a 5-year period, with no more than five taken per year and to target only whales
migrating through the Tribe’s usual and accustomed fishing grounds off the northwestern end of the
Olympic Peninsula (NMFS 2015). Two main concerns with the proposed hunt include the possible impact
on the PCFG as well as the possible taking of migrant individuals from the endangered WNP population.
In 2015, NMFS released a revised draft environmental impact statement analyzing the Tribe’s proposal and
other alternatives (NMFS 2015) and continues to review the Tribe’s request.
Species management and recovery planning. In addition to the WCA responsibilities noted above,
NMFS manages both stocks in U.S. waters under the MMPA and regularly assesses population sizes, trends,
and sources of mortality to guide conservation of the species (Carretta et al. 2019). NMFS also has ESA
jurisdiction for WNP gray whales. A draft conservation plan for the WNP population was prepared under
the auspices of the IWC and IUCN in 2010, with an update underway. The IUCN has also established a
February 2021 Washington Department of Fish and Wildlife
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